Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physics-Uspekhi

Geometrical phase effects in neutron optics

V. I. Bodnarchuk, Levon S. Davtyan, D.A. Korneev

Published Feb 28, 1996• 19 citations
Publisher

Abstract

The aim of this paper is to study in detail the geometric phase (Berry phase) and to discuss peculiarities of its measurements in the most typical physical case, i.e., the problem of neutron spin evolution in a precessing magnetic field.
DOI
10.1070/pu1996v039n02abeh000133

Related papers

Geometric phase of very slow neutrons

Erik Sjöqvist

The geometric phase (GP) acquired by a neutron passing through a uniform magnetic field elucidates a subtle interplay between its spatial and spin degrees of freedom. In the standard setup using thermal neutrons, the kinetic energy is much larger than the typical Zeeman split. This causes the spin to undergo nearly perfect precession around the axis of the magnetic field and the GP becomes a function only of the corresponding cone angle. Here, we perform a plane wave analysis of the GP of very slow neutrons, for which the precession feature breaks down. Purely quantum-mechanical matter wave effects, such as resonance, reflection, and tunneling, become relevant for the behavior of the GP in this low energy scattering regime.

arXiv:2003.13737•Mar 30, 2020•0 citations

Measurement of Berry’s phase for noncyclic evolution

Harald Weinfurter, G. Badurek

Tracing the neutron spin on its passage through a magnetic field which rotates at various frequencies it was possible to observe geometrically induced phase shifts of a quantum-mechanical state even for incomplete revolutions of this field. The experiments show that we can extract such purely geometric effects also from nonadiabatic evolutions.

Physical Review Letters•Mar 19, 1990•88 citations

The Berry phase: A simple derivation and relation to the electric dipole moment experiments with ultracold neutrons

V. K. Ignatovich

I derive the effective phase of the spin precession for a neutral particle with spin 1∕2 moving in a superposition of constant and radio frequency fields. The fields are perpendicular to each other at all times, and the radio frequency field is slowly rotating with angular speed ω. The derivation is accomplished with the help of the exact solution of the Schrödinger equation. I show that the geometrical (or Berry) phase is the linear term in the power series expansion of the effective phase in terms of ω. I also discuss the role of the Berry phase in the experimental search for an electric dipole moment of the neutron with ultracold neutrons.

American Journal of Physics•Feb 11, 2008•1 citation

New aspects of geometric phases in experiments with polarized neutrons

S Sponar, J Klepp, K Durstberger-Rennhofer +7 more

Geometric phase phenomena in single neutrons have been observed in polarimeter and interferometer experiments. Interacting with static and time dependent magnetic fields, the state vectors acquire a geometric phase tied to the evolution within spin subspace. In a polarimeter experiment the non-additivity of quantum phases for mixed spin input states is observed. In a Si perfect-crystal interferometer experiment appearance of geometric phases, induced by interaction with an oscillating magnetic field, is verified. The total system is characterized by an entangled state, consisting of neutron and radiation fields, governed by a Jaynes-Cummings Hamiltonian. In addition, the influence of the geometric phase on a Bell measurement, expressed by the Clauser-Horne-Shimony-Holt (CHSH) inequality, is studied. It is demonstrated that the effect of geometric phase can be balanced by an appropriate change of Bell angles.

arXiv:1002.0040•Journal of Physics A Mathematical and Theoretical•Aug 12, 2010•6 citations

New aspects of geometric phases in experiments with polarized neutrons

Stephan Sponar, Jürgen Klepp, Katharina Durstberger-Rennhofer +7 more

Geometric phase phenomena in single neutrons have been observed in polarimeter and interferometer experiments. Interacting with static and time dependent magnetic fields, the state vectors acquire a geometric phase tied to the evolution within spin subspace. In a polarimeter experiment the non-additivity of quantum phases for mixed spin input states is observed. In a Si perfect-crystal interferometer experiment appearance of geometric phases, induced by interaction with an oscillating magnetic field, is verified. The total system is characterized by an entangled state, consisting of neutron and radiation fields, governed by a Jaynes-Cummings Hamiltonian. In addition, the influence of the geometric phase on a Bell measurement, expressed by the Clauser-Horne-Shimony-Holt (CHSH) inequality, is studied. It is demonstrated that the effect of geometric phase can be balanced by an appropriate change of Bell angles.

•Sep 3, 2010•2 citations

General Solutions of Geometric Phase of Neutron in Rotating Magnetic Fields

Chen Xiaoyu

The exact solutions of the closed evolution of spin states in rotating magnetic fields are described for the most general cases via eigenstate method. A simple algorithm for calculating the geometric phase is exploited.

Communications in Theoretical Physics•Sep 15, 1998•0 citations
The geometric phase (GP) acquired by a neutron passing through a uniform magnetic field elucidates a subtle interplay between its spatial and spin degrees of freedom. In the standard setup using thermal neutrons, the kinetic energy is much larger than the typical Zeeman split. This causes the spin to undergo nearly perfect precession around the axis of the magnetic field and the GP becomes a function only of the corresponding cone angle. Here, we perform a plane wave analysis of the GP of very slow neutrons, for which the precession feature breaks down. Purely quantum-mechanical matter wave effects, such as resonance, reflection, and tunneling, become relevant for the behavior of the GP in this low energy scattering regime.
I derive the effective phase of the spin precession for a neutral particle with spin 1∕2 moving in a superposition of constant and radio frequency fields. The fields are perpendicular to each other at all times, and the radio frequency field is slowly rotating with angular speed ω. The derivation is accomplished with the help of the exact solution of the Schrödinger equation. I show that the geometrical (or Berry) phase is the linear term in the power series expansion of the effective phase in terms of ω. I also discuss the role of the Berry phase in the experimental search for an electric dipole moment of the neutron with ultracold neutrons.
Geometric phase phenomena in single neutrons have been observed in polarimeter and interferometer experiments. Interacting with static and time dependent magnetic fields, the state vectors acquire a geometric phase tied to the evolution within spin subspace. In a polarimeter experiment the non-additivity of quantum phases for mixed spin input states is observed. In a Si perfect-crystal interferometer experiment appearance of geometric phases, induced by interaction with an oscillating magnetic field, is verified. The total system is characterized by an entangled state, consisting of neutron and radiation fields, governed by a Jaynes-Cummings Hamiltonian. In addition, the influence of the geometric phase on a Bell measurement, expressed by the Clauser-Horne-Shimony-Holt (CHSH) inequality, is studied. It is demonstrated that the effect of geometric phase can be balanced by an appropriate change of Bell angles.
Geometric phase phenomena in single neutrons have been observed in polarimeter and interferometer experiments. Interacting with static and time dependent magnetic fields, the state vectors acquire a geometric phase tied to the evolution within spin subspace. In a polarimeter experiment the non-additivity of quantum phases for mixed spin input states is observed. In a Si perfect-crystal interferometer experiment appearance of geometric phases, induced by interaction with an oscillating magnetic field, is verified. The total system is characterized by an entangled state, consisting of neutron and radiation fields, governed by a Jaynes-Cummings Hamiltonian. In addition, the influence of the geometric phase on a Bell measurement, expressed by the Clauser-Horne-Shimony-Holt (CHSH) inequality, is studied. It is demonstrated that the effect of geometric phase can be balanced by an appropriate change of Bell angles.